Question
In Bainbridge mass spectrograph a potential difference of $1000 V$ is applied between two plates distant $1$ cm apart and magnetic field in $B = 1T$. The velocity of undeflected positive ions in m/s from the velocity selector is
✓
Answer
(c) $v = \frac{E}{B}$; where $E = \frac{V}{d} = \frac{{1000}}{{1 \times {{10}^{ - 2}}}} = {10^5}\,V/m$
==> $v = \frac{{{{10}^5}}}{1} = {10^5}m/s$.
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